# Not all 20 mm rails are real “80/20” rails and may not work for mini buttons.

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#### BABAR

##### Builds Rockets for NASA
TRF Supporter
On the left is the cross section of the four foot rail that I got from the link from railbuttons.Com which fits the mini button perfectly. I wanted to get a longer 6 ft rail as I wanted to get something to launch my Interceptor E on.

I found one and ordered it only to find as you can see here that the space is just too wide and the mini but just falls out.

What I will probably do is create a larger custom washer out of a hotel Key card unless someone has some advice on larger nylon and watching washers that will fit. May drop by Ace Hardware. They're very helpful. Lowe's and Home Depot now seemed to be just too busy to have as many people who are actually helpful.

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#### BABAR

##### Builds Rockets for NASA
TRF Supporter

here's the link for what I got that didn't work. I'm not knocking the company. Just not sure how I could have known before I ordered it that it would not work.

#### NateB

##### Well-Known Member
How does the product you received compare to the specs listed on 80/20's website?

$15 for a 6' rail, but shipping is probably a deal breaker. Their site quotes$24 shipping to me and I am about a 20-30 minute drive from their factory.

#### RocketScott

##### Active Member
TRF Supporter
You'll probably have better luck at McMaster-Carr finding exactly the right diameter washers. HD and Lowes is a crap shoot for what the outer diameter will be

I ran into a similar problem a while ago when Bosch started making 1" extrusions to compete with 80/20. The outside dimensions were the same but the groove was wider and regular buttons would fall out. I got a sample first and found out before placing a big order

#### David Schwantz

##### Well-Known Member
TRF Supporter
There mini buttons and micro buttons. Could you just go up on the button size?

#### Titan II

##### Well-Known Member
The title of this thread is misleading. 80/20 is a brand. You did not buy an 80/20 rail.

You also mention that you were not sure how you could have known before hand that it would not work. All dimensions including the slot are identified in the ad.

#### RocketRohde

##### Well-Known Member
I went to Lowes and bought size #8 nylon washers, should be good to go.

#### kuririn

##### BARGeezer
TRF Supporter
For most mid power birds a 6 ft.1010 rail is more than sufficient.
Since you fly mostly LPR with the occasional MPR the rail from erockets that you have already is all you need.
Just my 2 cents.

#### BABAR

##### Builds Rockets for NASA
TRF Supporter
The title of this thread is misleading. 80/20 is a brand. You did not buy an 80/20 rail.

You also mention that you were not sure how you could have known before hand that it would not work. All dimensions including the slot are identified in the ad.
You are correct, and I have adjusted the title accordingly.

My hope is to prevent others from going down the same path.

Since I bought the item I can’t get back to the original page. But the other 20 mm rail from that vendor DO have the dimensions, I ASSUMED (incorrectly) that if the outer dimensions matched the inner ones would as well. I thought there was some sort of standard and was incorrect.

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#### zog139

##### Well-Known Member
I would like to buy two 4' pieces of 20mm rail and a connector to attach them for an 8' rail for mini buttons. I haven't been able to find a good link to buy from ? The rail buttons site says they are temporarily closed.

#### BABAR

##### Builds Rockets for NASA
TRF Supporter
I would like to buy two 4' pieces of 20mm rail and a connector to attach them for an 8' rail for mini buttons. I haven't been able to find a good link to buy from ? The rail buttons site says they are temporarily closed.

Can buy single lengths up to 102 inches. What I SHOULD have done in first place, $50 with shipping Two 4 foot lengths is$50.50 with shipping.

#### zog139

##### Well-Known Member
Thanks, for the link. Did you order from one if the vendors or direct from that site? Sometimes looking on the phone is not the best for browsing.

Can buy single lengths up to 102 inches. What I SHOULD have done in first place, $50 with shipping Two 4 foot lengths is$50.50 with shipping.

#### Rocketless

##### Member
On the left is the cross section of the four foot rail that I got from the link from railbuttons.Com which fits the mini button perfectly. I wanted to get a longer 6 ft rail as I wanted to get something to launch my Interceptor E on.

I found one and ordered it only to find as you can see here that the space is just too wide and the mini but just falls out.

What I will probably do is create a larger custom washer out of a hotel Key card unless someone has some advice on larger nylon and watching washers that will fit. May drop by Ace Hardware. They're very helpful. Lowe's and Home Depot now seemed to be just too busy to have as many people who are actually helpful.
Here you go
From 80/20 you can do 2 mini rails

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#### BABAR

##### Builds Rockets for NASA
TRF Supporter
Thanks, for the link. Did you order from one if the vendors or direct from that site? Sometimes looking on the phone is not the best for browsing.
I ordered a knock off, actually posted here on forum and was suggested it should work. I figured 20 mm was 20 mm, I had assumed that the internal dimensions would be the same, as I think these are designed for other construction purposes (with Rocketry being a good but far from intended purpose) and the grooves would be standardized. They are NOT.

The internal dimensions WERE posted (I did NOT get ripped off), I just didn’t do enough of my own homework.

#### BABAR

##### Builds Rockets for NASA
TRF Supporter
Okay, side by side comparison. Take home lesson is that if you look to save money on a knock off, make sure you check the cross sectional diameters, as at last THIS one didn't work.

Hopefully others will learn from my mistake.

View attachment 440911
The "slot" on the "real" 80/20 rail is 5.26 mm compared with 6.2 mm on the ZYLtech. This is probably the main reason the buttons won't work on the Knock-Off Rail.
The "internal width" of the slot on the 80/20 is 11.99mm compared with 11 on the ZYLtech
The "depth" of the slot on the 80/20 is 4.70mm compared with 4.3 mm on the ZYLtech.

Bottom line is that the Mini-Buttons will fit in the slot of the ZYLtech, but the outlet of the slot is too wide, and with a minimal twist/angulation of the button the button falls out of the hole.

I am going to ask @Angie to copy this as post number 2 on this and the other post I put in about my plaint that what I got doesn't work for the mini-rail buttons from Rail-Buttons.com. Note currently the SITE is up but Randy is (per the site) not filling orders until the new year due to rotator cuff surgery.

Here is a side by side cross section comparison of the 80/20 Rail from the

sources of above information.

80/20 Store 20 mm rail

ZYLtech rail from e-bay

and yes, the information WAS there when I ordered it, I just didn't know that there were any differences, I figured they all had the same dimensions.

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#### Sluggo

##### Well-Known Member
About these rails.... Do they slide down over a 1/4" launch rod.?? I'm hoping..... Yes.

#### crossfire

Just buy from 80/20 store might cost more but it will work.

#### Titan II

##### Well-Known Member
About these rails.... Do they slide down over a 1/4" launch rod.?? I'm hoping..... Yes.
The dimensions on the drawings answer your question. Here is another drawing for an 80/20 1010.

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#### Sluggo

##### Well-Known Member
Yes and no. What is 0 (w/slash) 5.?? 5mm.?? Um, no.

#### Sluggo

##### Well-Known Member
Yes and no. What is.... 0(w/slash) 5.?? 1/4".?? Um, no. So I guess the answer is no, I guess. That's why I asked here but I guess you're no help. Or a school teacher.

#### RocketScott

##### Active Member
TRF Supporter
Yes and no. What is.... 0(w/slash) 5.?? 1/4".?? Um, no. So I guess the answer is no, I guess. That's why I asked here but I guess you're no help. Or a school teacher.
The 0 w/slash denotes the diameter

If the hole is 5mm you might be able to drill it out to 1/4”. Maybe tapping it for 1/4” and threading in a bolt with a shoulder would work

#### Sluggo

##### Well-Known Member
0 with slash denotes the diameter. Huh.?? I thought the 5 would be the diameter. I think I know what you're saying. Ha.!! Thanks for the reply.

I need confirmation..... These button rails are designed to slip onto a launch rod, correct.??

#### BABAR

##### Builds Rockets for NASA
TRF Supporter
About these rails.... Do they slide down over a 1/4" launch rod.?? I'm hoping..... Yes.
Center hole barely fits 1/8”, not sure if it will make 3/16. Definely won’t make 1/4 through center hole.

Anybody try slipping a 1/4 rod into one of the side slots? Somebody has shown earlier that the 80/20 rail DOES slide into a 10/10 rail.

You could drill lateral holes at each end (or one end and just shorter than length of the 1/4 rod, if rod is shorter than rail) in opposite slots to run a wire through and wire it onto your 1/4 rod. You’d have one free unencumbered slot opposite the rod for the rocket , one slot fixed against the rod, other two with wires. Should be pretty easy.

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#### beeblebrox

##### 8 C6-0, 12 D11-9, 20 D20-0, 20 E5-0, 3 Cinerocs
Okay, side by side comparison. Take home lesson is that if you look to save money on a knock off, make sure you check the cross sectional diameters, as at last THIS one didn't work.

Hopefully others will learn from my mistake.

View attachment 440911
The "slot" on the "real" 80/20 rail is 5.26 mm compared with 6.2 mm on the ZYLtech. This is probably the main reason the buttons won't work on the Knock-Off Rail.
The "internal width" of the slot on the 80/20 is 11.99mm compared with 11 on the ZYLtech
The "depth" of the slot on the 80/20 is 4.70mm compared with 4.3 mm on the ZYLtech.

Bottom line is that the Mini-Buttons will fit in the slot of the ZYLtech, but the outlet of the slot is too wide, and with a minimal twist/angulation of the button the button falls out of the hole.

I am going to ask @Angie to copy this as post number 2 on this and the other post I put in about my plaint that what I got doesn't work for the mini-rail buttons from Rail-Buttons.com. Note currently the SITE is up but Randy is (per the site) not filling orders until the new year due to rotator cuff surgery.

Here is a side by side cross section comparison of the 80/20 Rail from the

sources of above information.

80/20 Store 20 mm rail

ZYLtech rail from e-bay

and yes, the information WAS there when I ordered it, I just didn't know that there were any differences, I figured they all had the same dimensions.

https://www.rocketryforum.com/threads/not-all-20-mm-rails-are-real-“80-20”-rails-and-may-not-work-for-mini-buttons.163031/#post-2071101 will also be fixed.View attachment 440918View attachment 440918
What you are missing, is that 3D printers use the metric 2020 rails (20mm square) commonly. Rocket flyers use 1010 rails which are 1" square or 1515 rails which are 1.5" square. Standard rail buttons do not fit 2020 rails and if you make a button to fit those they wont work on 1010 rails. if you build to 2020 rails then you will have a problem when attending a club launch or any major launch around the country. Just make a block to bolt to the side of the 1010 rail if it doesn't fit over the rod. Or, just make a mount for fit the 1010 rail directly. The rod idea is not that good anyway, too flexible. You want a rail mounted firmly.

#### T-Rex

##### Ordinary Average Guy
TRF Supporter
0 with slash denotes the diameter. Huh.?? I thought the 5 would be the diameter. I think I know what you're saying. Ha.!! Thanks for the reply.

I need confirmation..... These button rails are designed to slip onto a launch rod, correct.??
Yes in the illustration above the diameter of the center hole is 5mm diameter. (however that is the knock off rail that did not fit the buttons)
No you cannot slide a rail over a 1/4" rod.
You will need to find a way to mount your rail solidly to a base. (drill through holes and bolt it to something, use some sort of clamp, etc) This is largely dependent on your support/stand design. The rails are not made for rockets, they are made for construction. We just happened to figure out a way to adapt them to our purpose. YOU will have to design a support system for it.

#### T-Rex

##### Ordinary Average Guy
TRF Supporter
What you are missing, is that 3D printers use the metric 2020 rails (20mm square) commonly. Rocket flyers use 1010 rails which are 1" square or 1515 rails which are 1.5" square. Standard rail buttons do not fit 2020 rails and if you make a button to fit those they wont work on 1010 rails. if you build to 2020 rails then you will have a problem when attending a club launch or any major launch around the country. Just make a block to bolt to the side of the 1010 rail if it doesn't fit over the rod. Or, just make a mount for fit the 1010 rail directly. The rod idea is not that good anyway, too flexible. You want a rail mounted firmly.
Mini rail buttons are designed to fit the 2020 series of extrusion. (20mm square).
Micro buttons are designed to fit the Maker Beam 10mm extrusion.

The rest of you comment is valid in that most clubs do not have 2020 or Maker Beam rails. Mine will soon, because I will be providing it.